make sure we order the correct lens diameter for our patient. according to MSU.

If our MSU is 60mm, we have to order lens with diameter of 60mm (only if the manufacturer produce this diameter), if not, you can order lens with diameter of 65mm, do not order lens with 70 or 75mm! (you can do so if only 65mm lens is not available).larger the diameter, the great price it will be.